Islamic economic system covers various aspects of economic activity, one of which is the sale. Economic development at the present time as buy-sell various agricultural systems that blow occurred in the village Tasikharjo. The practice of buying and selling by way of this blow has been around since ancient times and has become a habit. In Islamic trading is the exchange of certain assets with other assets based on the pleasure of both, selling it is prescribed by the consensus of the Muslims because human life can not be upright without selling.

This study aims to determine how the implementation of the agreement in the agricultural system in the Village blow Tasikharjo Jenu Tuban district at the present time and how the implementation of the contract in the blow of the system according to the Shafi'i Fiqh view. To achieve these objectives the study researchers used a type of qualitative descriptive approach. While the data collected in the form of primary data and secondary data was done by using interviews, observation and documentation. Test the validity of data using triangulation and data analysis using descriptive with several stages of checking the data, grouping, inspection, data analysis, and conclusions.

The results of this study indicate that the system blow that occurred in the village of Tasikharjo, agreement means a wide variety of contract can be done at home on both sides both farmers and buyers, or covenant may occur in the field after the buyer saw the plants and take samples of plants, and at last the contract existing plants in the fields belonged to the buyer of the goods or property that has changed hands but it is to know that not all agricultural crops can be sold and bought by blow. If the terms of pillars according to the Syafi'i fiqh can all be met, but when viewed in terms of condition, blow agricultural system in the village of Tuban Jenu District Tasikharjo less qualified, the payment should be paid in full upfront there does not apply and if the plants that have been purchased are not desirable, can not be replaced with plants that price or the same type. Although practically less qualified, but the sale of these developments may be legal, because the goods traded halal and also protected from fraudulent behavior (gharar), which can lead to quarrels in the future, and also keep in mind that it's basically a buy- sell agreement in which the most important is the element of mutual pleasure.